Increased rupture risk in small intracranial aneurysms associated with methamphetamine use.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (SAH) is the most common cause of nontraumatic SAH. Current guidelines generally recommend observation for unruptured intracranial aneurysms smaller than 7 mm, for those are considered at low risk for spontaneous rupture according to available scoring systems. OBJECTIVE: We observed a tendency for SAH in small intracranial aneurysms in patients who are methamphetamine users. A retrospective, single center study to characterize the size and location of ruptured and unruptured intracranial aneurysms in methamphetamine users was performed. MATERIALS AND METHODS: Clinical characteristics and patient data were collected via retrospective chart review of patients with intracranial aneurysms and a history of methamphetamine use with a specific focus on aneurysm size and location. RESULTS: A total of 62 patients were identified with at least one intracranial aneurysm and a history of methamphetamine use, yielding 73 intracranial aneurysms (n = 73). The mean largest diameter of unruptured aneurysms (n = 44) was 5.1 mm (median 4.5, SD 2.5 mm), smaller than for ruptured aneurysms (n = 29) with a mean diameter of 6.3 mm (median 5.5, SD 2.5 mm). Aneurysms measuring less than 7 mm presented with SAH in 36.5%. With regard to location, 28% (n = 42) of anterior circulation aneurysms less than 7 mm presented with rupture, in contrast to 70% (n = 10) of posterior circulation aneurysms which were found to be ruptured. CONCLUSIONS: Methamphetamine use may be considered a significant risk factor for aneurysmal SAH at a smaller aneurysm size than for other patients. These patients may benefit from a lower threshold for intervention and/or aggressive imaging and clinical follow-up.

Imaging depletion: fMRI provides new insights into the processes underlying ego depletion*.

'Ego depletion' refers to the phenomenon of diminished ability to enact self-regulation with repeated efforts. Several models offer process accounts of how ego depletion works, but few studies directly investigate these processes. A study in this issue of Social, Cognitive, & Affective Neuroscience by Wagner and Heatherton is among the first to do so. Their results substantiate one possible mechanism of ego depletion and, more broadly, illustrate how neuroscience data can further social psychological theory.

Computed tomographic angiography in evaluation of superficial temporal to middle cerebral artery bypass.

Catheter-directed digital subtraction angiography (DSA) is considered the standard for evaluation of superficial temporal to middle cerebral artery (STA-MCA) bypass patency. Few clinical investigations have been performed that evaluate the efficacy of computed tomographic angiography (CTA) in the assessment of extracranial-intracranial bypass. Using multi-detector row CTA, STA-MCA bypass patency was assessed in the initial postoperative period and several months afterward and compared with DSA. No significant difference was identified in the evaluation of graft patency between DSA and CTA. Although multiple modalities exist to evaluate STA-MCA bypass graft patency, the multidetector CTA is widely available and allows for rapid, accurate patency assessment.

Management of giant middle cerebral artery aneurysms with incorporated branches: partial endovascular coiling or combined extracranial-intracranial bypass--a team approach.

OBJECTIVE: Our goal was to assess the long-term anatomic and clinical outcomes in patients with giant middle cerebral artery (MCA) aneurysms treated by endovascular coil embolization alone or in combination with cerebral revascularization. METHODS: One hundred twenty-six patients with giant intracranial aneurysms were endovascularly treated at the University of California, Los Angeles, between 1990 and 2007. Of these, 9 patients had partially thrombosed MCA aneurysms with incorporated branches. Five patients presented with symptoms of mass effect, 3 had seizures, 2 had episodes of brain ischemia, and 1 presented with acute subarachnoid hemorrhage. RESULTS: Three wide-neck saccular aneurysms were almost completely coil occluded, leaving only small neck remnants that were intended to preserve the patency of incorporated MCA branches. The other 6 fusiform aneurysms were effectively treated by superficial temporal artery-MCA or occipital artery-MCA bypass, followed by complete coil occlusion of these aneurysms. Immediate angiograms and mid- or long-term neuroradiological imaging follow-up examinations revealed complete obliteration or near-complete occlusion (90%-99%) of the aneurysms in all 9 patients. Seven patients had a favorable long-term clinical outcome, and 1 patient died as a result of unrelated congestive heart failure. One patient required emergent surgical aneurysm thrombectomy because of inadvertent coil occlusion of the frontal opercular artery, which was not protected by the bypass, and the patient subsequently sustained a moderate neurological disability. CONCLUSION: Giant MCA aneurysms with branch incorporations and other unfavorable features such as intraluminal thrombus, mural calcification, and fusiform configuration can be effectively treated with a team approach, using coil embolization after protective surgical bypass. When aneurysms with MCA branches incorporated into the neck rather than the dome are treated by endovascular techniques alone, long-term angiographic follow-up is necessary to assess and further treat any significant remnant.

Combined covered stent and onyx treatment for complex dural arteriovenous fistula involving the clivus and cavernous sinus.

BACKGROUND: Complex DAVFs involving both the clivus and cavernous sinus are rare, especially when associated with brainstem compression from a large varix. In this report, we describe the use of a covered stent in combination with a liquid embolic agent to cure a complex clival-cavernous DAVF. METHODS: A 46-year-old man presented with 6 months of dizziness, dysphagia, and progressive dysarthria. Magnetic resonance imaging showed tortuous and enlarged right cavernous and preclival flow voids. There were also bilateral prepontine varices compressing the ventral pons, which led to marked dorsal pontine edema. A cerebral angiogram revealed a clival DAVF supplied by multiple branches of the right ECA, as well as the MHT of the right ICA. RESULTS: An endovascular cure was achieved by deploying a covered stent in the right cavernous ICA, followed by transarterial embolization of the feeding arteries originating from the ECA with Onyx (ev3, Irvine, Calif). This combined approach resulted in complete occlusion of the fistula. His 1-month follow-up angiogram confirmed persistent occlusion of the fistula and preserved patency of the right ICA. The patient made a full recovery without any new symptoms, and he remained neurologically intact at 18-month follow-up. CONCLUSION: The combined technique of covered stent placement and Onyx transarterial embolization is valuable for the management of complex DAVFs supplied by branches of both the external and internal carotid arteries.

Transarterial embolization of clival dural arteriovenous fistulae using liquid embolic agents.

OBJECTIVE: Dural arteriovenous fistulae (DAVFs) rarely involve the clivus. This report examines the clinical presentation, angiographic findings, endovascular management, and outcome of clival DAVFs. Particular attention was given to safety and efficacy of transarterial embolization using liquid embolic agents. METHODS: We reviewed the clinical and radiological data of 10 patients with spontaneous clival DAVFs who were treated endovascularly at the University of California at Los Angeles Medical Center between 1992 and 2006. RESULTS: Nine patients presented with ocular symptoms and one patient experienced pulsatile tinnitus. Cerebral angiograms showed that these clival DAVFs were supplied by multiple branches of the internal and external carotid arteries. The patterns of venous drainage were from the clival veins to the cavernous sinus and superior ophthalmic vein in nine patients and to the inferior petrosal sinus in two patients. Six clival DAVFs were embolized transarterially through the clival branches of the ascending pharyngeal artery. Onyx 18 (Micro Therapeutics Inc., Irvine, CA) was used in three patients and n-butyl cyanoacrylate was used in three patients. Immediate complete angiographic obliteration was achieved in three patients. All six patients experienced an angiographic and clinical cure without any complications at 3 months. Two patients were incompletely treated using particles and coils for the relief of the symptoms. Two other patients were completely treated after the recipient clival venous structures were occluded transvenously with coils. CONCLUSION: Clival DAVFs can be misdiagnosed as dural cavernous sinus fistulae. The best treatment is transarterial embolization of the dural feeders using liquid embolic agents. Transvenous occlusion of the cavernous sinus is unnecessary in most cases.